You know the drill: The breast self-exam (BSE) illustrations on those pamphlets usually show a woman with one arm up over her head, pushing the fingers of her other hand across her breastin search of a lump or some other sort of change. Your ob-gyn may have talked to you about doing this every month at home, ideally at a time when your breasts don't feel tender or swollen.

BSE controversyThe truth is, even doing regular BSEs (without regular mammograms) may not protect you. A large study conducted in China by researchers from the Fred Hutchinson Cancer Research Center in Seattle made headlines in 2002 by suggesting that women who were taught to do regular BSEs didn't fare any betteror live any longerthan women who were not taught to do them. On average, they didn't find cancer any earlier. Still, many medical experts believe women should familiarize themselves with how their breasts feel.

Dense breastsBSEs can be tricky for women with dense breast tissuewhich is common for younger women. "Mostly they don't know what they're feeling or are not confident," says Janet Wolter, MD, a medical oncologist and the Brian Piccolo Chair of Breast Cancer Research at Rush University Medical Center in Chicago. "The breast is constructed like an orange or a grapefruit; you'll feel segments, and that's scary, but it's normal."

BSEs as you ageFor premenopausal women, "the easiest day to remember to do a BSE is the first day of your cycle, when you get your period," suggests Julia A. Smith, MD, director of the NYU Cancer Institute's breast cancer screening and prevention program and director of the Lynne Cohen breast cancer preventive care program at NYU in New York City. If you feel something, wait two weeks and then do another BSE. The odds are it'll be gonebreast tissue often changes throughout the menstrual cycle, says Dr. Smith. But if the abnormality persists, you should see your doctor.

Older women generally have easier BSEs, because after menopause the tissue gets much softer: "If you put a Ping-Pong ball in there, you'd feel it right away," as Dr. Wolter puts it.